A semiconductor laser device has a multilayer structure including a first
clad layer, an active layer, and a second clad layer stacked successively
on a semiconductor substrate in order of increasing distance from the
semiconductor substrate. At least one of the first clad layer and the
second clad layer has a compressive distortion with respect to the
semiconductor substrate. At least one of the first clad layer and the
second clad layer includes a semiconductor layer having a tensile
distortion with respect to the semiconductor substrate.